Material working apparatus



Jan. 8, 1946.

P. KOMROFF ET AL MATERIAL WORKING APPARATUS Filed June 28, 1944 2 Sheets-Sheet 1 Jan. 8, 1946. P. KOMROFF ETAL MATERIAL WORKING APPARATUS 2 Sheets-Sheet 2 Filed June 28, 1944 '5'. 1 /77- 0. MWATF/P-S' 57 8R ATTORA/f/ Patented Jan. 8, 1946 MATERIAL'WORKING APPARATUS Paul Komrofl, Flushing, N. Y., and Samuel Pitt, Westfleld. and Daniel Vaughn Waters, Flemington, N. J., asslgnors to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application June 28, 1944, Serial No. 542,566

6 Claims.

This invention relates to material working apparatus, and more particularly to apparatus for cutting glass tubes into predetermined lengths.

In the manufacture of articles such as vacuum tubes, lamps or the like wherein glass tubes of iven lengths are employed, the latter are fre quently cut from lengths of tubing through the aid of abrasive wheels such as Carborundum or diamond studded wheels. To accomplish the best results it has been found that the glass tubes may be out most efficiently by the abrasive wheels rotating at a given peripheral speed. Due to the rapid-wearing of abrasive wheels of this type, the peripheral speed thereof varies rapidly if the abrasive wheels are rotated at a constant speed.

An object of the invention is to provide a material working apparatus particularly adapted for cutting glass wherein eflicient means maintains a constant peripheral speed of the cutting means.

With this and other objects in view,- the invention comprises a material working apparatus including a rotatable material working element variable in peripheral dimensions with wear, a support to move material relative to the element to cause cutting of the material, and means to vary the rotary speed of the element with its variation in peripheral dimensions to maintain a substantially constant peripheral speed'of the element.

Other objects and advantages will be apparent from the following detailed description when considered in conjunction with the accompanying drawings, wherein Fig. 1 is a side elevational view of the apparatus, portions thereof being broken away;

Fig. 2 is a fragmentary sectional view taken substantially along the line 22 of Fig. 1, and

Fig. 3 is a fragmentary front elevational View taken substantially along the line 33 of Fig. 1.

Referring now to the drawings, the apparatus includes a supporting frame upon which a bracket H is mounted, the latter having an upper bearing portion |2 to rotatably support a shaft l4. At the inner end of the shaft I4 a fixed mounting plate I5 is disposed to cooperate with a removable mounting plate I6 through the aid of a retaining screw H for use in mounting a material working or cutting element l8 upon the shaft. The element I8 is an abrasive wheel formed of Carborundum, diamond particles or the like adapted for use in cutting glass tubes or other like material.

At the outer end of the shaft H a pulley is mounted for operative connection with a variable pulley indicated generally at 2| through the aid of a belt 22. The variable pulley, 2| is driven by a motor 23 and includes a variable speed control unit 24 of any commercially known type. The unit 24 with its pulley 2| is well known in the art, and it is'believed that a detailed description and illustration thereof are I not essential for a complete understanding of the invention. It should be understood, however, that the spring control mechanism within the unit 24 allows movement of pulley members 25 and 26 relative to each other cooperating to provide a V-shaped pulley groove 21 which varies with variation in the position of the axis of the motor or the motor shaft, upon which this structure is mounted, relative to the axis of the shaft l4.

The 'motor 23 is mounted upon a support 3|), hanging from a shaft 3| and fixed thereto as at 32(Fig. 3). The shaft 3| is journalled in suit-. able bearings 33 of the frame Ill and has a lever arm 34 fixed thereto as illustrated in Fig. 1. A yoke 35 is pivotally connected, as at 36, to the outer end of the lever arm 34 and has a portion 31 centrally apertured for free rotation upon a threaded control shaft 38 between a pair of fixed collars 39. The outer end of the threaded shaft 38 has a crank 40 fixed thereto for manual actuation of the shaft, to rotate it relative to a threaded element 4| through which a. threaded portion 42 of the shaft extends. The threaded element 4| is held in a given position by journal portions 44 integral with the frame l0, only one of which is shown in Fig. 1, to enable the element to pivot or rotate the necessary distance for the movement of the threaded shaft in moving the lever arm 34 to vary the position of the motor 23.

Locating collars 46 and 4! are fixedly mounted upon the threaded shaft 38 atgiven spaced positions to control the movement of a material support indicated generally at 50. The material support is U-shaped in general contour, as illustrated in Fig. 3, and includes a central portion 5|, angular in cross-section, with leg portions 52 which extend downwardly, their lower-ends being apertured for mounting, as at 53, upon the outer ends of a. supporting rod or shaft 54. The rod 54 is journalled in suitable bearings 55 mounted upon the frame It! and has a control arm 51 fixedly mounted thereon as illustrated in Fig. 3. The lower end of-the control arm 51 is bifurcated, as at 58, to straddle thethreaded shaft 38, tapered surfaces 59 and 60 [thereof to receive the cutting element l8 so that it may cut completely through any article or material disposedon the support. A reenforced portion 63 extends about the slot 62. A variable stop or locating unit 65 is clamped at any suitable position upon the vertical part of the central portion of the material support, as, illustrated in Figs. 2 and 3, it beingheld in any desired position through the aid of a thumb screw 66. Another screw or threaded element .61 is included in the unit 65' to serve as a variable stop to locate the material, which in the present instance is a glass tube 68, on the support relative to the cutting element 18.

A lubricant is necessary in the present instance for the cutting element l8. This lubricant is supplied to both sides of the element through nozzles 10 extending from a joint connection 1| with a suitable supply means (not shown). A receptacle or reservoir 12 mounted upon the frame I0 receives the lubricant, a lip 13 of the reservoir extending forwardly beneath the material support 50. A drain 14 for the reservoir may be connected, if desired, with any recirculating means (not shown). A hood 15, in cooperation with its cover 16 removably secured in place by wing bolts 11 or the like, partially surrounds the cutting element to eliminate outward splashing of the lubricant. The hood and its cover are cut away, as at 18, so that the major portion of the cutting element may be utilized as its diameter decreases due to wear.

Considering now the operation of the apparatus, let it be assumed that the solid line illustration of the cutting element represents the full diameter thereof when new. The motor and its pulley unit 2| will at this time be in the solid line position shown in Fig. 1, causing rotation of the cutting element at a given peripheral speed.

At this time the limits of movement of the ma-.

' thereof, its position being controlled by the unit 65 or its screw 61. By holding the material at desired positions away from the slot 62, the operator may move the support about its pivot,

namely the bearings for the rod 54, to move the material into engagement with the rotating element until the latter cuts through the material. The material support may then be returned to its normal position, the length of the material removed therefrom, the material advanced again to the stop or screw 61, and the cutting operation repeated. During each movement of the support 50 in the inverted pendulum-like manner, it is controlled by the surfaces 59 and 60 of the control arm 58 engaging their respective collars 46 and 41.

As the cutting element wears, it is necessary for the operator-to adjust the locations of the collars 46 and 41, in order that the material may be completely severed. This adjustment is made through the aid of the crank 40, to rotate the threaded shaft 38 and thus move the collars 46 and 41 the desired distance. This distance is also controlled by the reenforcing structure 63 of the support 50. limiting the inward movement of the support. As previously stated, it is important that the peripheral speed of the cutting element be maintained substantially constant. This is substantially automatically brought about through the linking of the control means for moving the motor with the control means for the material support. During the adjustment of the collars 46 and 41 through the movement of the threaded shaft 38, the lever arm 34 is also moved to move the motor 23 arcuately together with its pulley unit 2|, to shorten the distance between the axis of the motor and its pulley unit 2| and the axis of the cutting element. The belt being of a constant size, will enable the control unit 24 to function to move the pulley members 25 and 26 closer together to increase the driving diameter of the variable pulley 2|, and thus'increase the speedof rotation of the cutting element l8. This variation continues for each adjustment of the threaded shaft made necessary to bring about variations in the positions of the collars 46 and 41. The extreme variation is illustrated in dot and dash lines in Fig. 1, where the driving diameter of the pulley members 25 and 26 has increased to substantially twice its original diameter, as illustrated in the solid lines in this figure. Furthermore, the dot and dash lines in the cutting element in Fig. 1 illustrate approximately theextreme wear of the element and also the position of the material 68 when severed by the cutting element reduced to this diameter.

It will, therefore, be understood that the material working or cutting element l8 decreases in peripheral dimensions with Wear, and through the aid of the threaded shaft 38 and its control means, the rotary speed of the cutting element may be increased with the decrease in the peripheral dimensions thereof to maintain a constant and peripheral speed thereof, all of this being accomplished through the variation in the control means for the material support. Furthermore, to install a new cutting element it is necessary to return the support 50 to its original position, thus making it impossible to cause driving of the new cutting element at an excessive peripheral speed.

Although specific -improvements of the invention have been shown and described, it will be understood that they are but illustrative and that various modifications may be made therein without departing from the scope and spirit of this invention as defined by the appended claims.

What is claimed is:

1. A material working apparatus comprising a material working element rotatable about a given axis, a, support for material mounted for movement toward and away from the axis of the element, between given limits, means to cause variation in the rotary speed of the element, and means under the control of the last named means to vary the limits of movement of the support.

2. A material working apparatus comprising a rotatable material cutting element decreasing in peripheral dimensions with wear, a support for material mounted for movement relative to the element, lbetween given limits, means to increase the rotary speed of the element with the decrease in the peripheral dimensions thereof to maintain a substantially constant peripheral speed of the element, and means under the control of the last named means to vary the limits of movement of the support.

3. A material working apparatus comprising a rotatable material cutting element decreasing in peripheral dimensions with wear, power means,

-with the decrease in the peripheral dimension of the element to maintain a substantially constant peripheral speed or the element, a support for the material movable toward and away from the element between given limits, and means under the control oi the last named means to vary the limits oi movement of the support. I

4. A material working apparatus comprising a rotatable material cutting element decreasing in peripheral dimensions with wear, a support pivotally mounted for movement of material toward and away from the element, a control member, stops carried by the control member to limit the movement of the support, means to actuate the control member to vary the positions or the stops relative to the element and thus vary the limits the support may be moved toward and away from the element, and means affected by the control member to cause variation in the peripheral speed of the cutting element. p

5. A material working apparatus comprising a rotatable material cutting element decreasing in peripheral dimensions with wear, a support pivotally mounted for movement of material toward and away Irom the element, a control member, stops carried by the control member to limit the movement of the support, means to actuate the control member to vary the positions of the stops relative to the element and thus vary the limits the support may be moved toward and away from the element, and means actuable by the control member to increase the rotary speed of the element with the decrease in the peripheral dimensions thereof to maintain a. substantially constant peripheral speed of the element.

6. A material working apparatus comprising a rotatable material cutting element decreasing in peripheral dimensions with work, a motor, means including a variable pulley to operatively connect the motor with the cutting element to cause rotation of the element when the motor is energized, means to support the motor for movement relative to the cutting element, a support pivotally mounted for movement of material toward and away from the element, a control member, stops carried by the control member to limit the movement of the support, means to actuate the control member to vary the positions of the stops relative to the element and thus vary the limits the support may be moved toward and away from the element and means actuated by the control member to move the motor relative to the cutting element to cause the variable pulley to increase the rotary speed 01' the cutting element.

PAUL KOMROFF. SAMUEL PITT. DANIEL VAUGHN WATERS. 

